1. Field of the Invention
The present invention relates to a torque sensor, and more particularly, to a torque sensor for improving precision when measuring force and torque.
2. Description of the Prior Art
Generally, a torque sensor is used for a wearable robot joint and a precision machining tool to measure force and torque, to perform more precise work and reduce risk factors that occur within an operating radius. As a result, a necessity for a torque sensor has increased.
Meanwhile, the force torque sensor is based on a principle of detecting deformation of an elastic structure in a sensor that occurs due to force required to measure force and torque. To detect deformation occurring in the elastic structure, a method of using a strain gauge has been developed, and a method of measuring deformation using a silicon MEMS sensor has been researched.
At present, the force torque sensor requires 10 to 20 strain gauges and calibrations for each sensor, and therefore is expensive. Recently, research has been conducted on a sensor capable of measuring force and torque in various manners to reduce sensor price without the need of a large number of strain gauges attached to a structure.
In the related art, as illustrated in FIG. 1, a method of coupling an elastic structure 10 between two shafts and detecting deformation that occurs in the elastic structure 10 due to the force generated between the shafts using several strain gauges 11 has been developed.
However, when the torque sensor according to the related art measures force and torque components based on output voltage using each strain gauge 11 configured in a bridge circuit and attached to the elastic structure 10, the torque sensor is easily manufactured, but it is difficult to precisely attach the strain gauge 11, causing a decrease in accuracy and error of about 5%.